Devices for monitoring an infant are currently available. However, most conventional infant monitors are little more than remote viewing and/or listening devices, using visible light image sensors (e.g., CMOS-based or CCD-based sensors) and/or microphones to passively provide images and/or sound of an infant to a caregiver. As such, these conventional infant monitors require the caregiver to keep a constant eye and ear on the monitor for any unusual condition or activity of the infant, which is practically impossible. Furthermore, even if the caregiver stands in a constant vigil in front of the monitor, it may still be very difficult, if not impossible, to detect abnormal conditions that may lead to death, injury, or other serious harm to the infant. For example, abnormal breathing patterns, including apnea, are a symptom as well as a cause of sudden infant death syndrome (SIDS), but abnormal breathing patterns are difficult to recognize through video images of the infant. In another example, while an abnormal body temperature may be a sign of serious illness that requires immediate attention, no temperature reading can be obtained through conventional video images.
While some conventional solutions may be available for limited active monitoring that detects movement, heartbeat, or temperature, these conventional solutions are based on techniques that require contact. That is, these solutions require patches and/or electrodes in direct contact with the body of the infant, patches and/or electrodes in diapers or clothes, sensor pads on mattresses, or other sensors in direct or indirect contact with the infant to detect temperature, movement, or heartbeat. Thus, contact-based solutions may not only be inconvenient but also restrict the choice of the monitoring location (e.g., only on a bed or in a crib).
Yet another disadvantage of conventional infant monitors is that active illumination is required for viewing at nighttime or other low light situations. Actively illuminated images of the infant are often washed out if the infant is close to the light source, and too dimly lit if the infant is far from the light source. Furthermore, light sources may add bulk to a camera module of infant monitors and quickly drain power sources (e.g., batteries), thereby limiting the portability of infant monitors.